From flea bites to galaxies, from love affairs to shadows, Paul Feyerabend reveled in the sensory and intellectual abundance that surrounds us. He found it equally striking that human senses and human intelligence are able to take in only a fraction of these riches. "This a blessing, not a drawback," he writes. "A superconscious organism would not be superwise, it would be paralyzed." This human reduction of experience to a manageable level is the...